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This article describes a method for electrodynamic modeling of strip radiating structures based on a chiral metamaterials using of an apparatus of hypersingular integral equations. A mathematical model of such radiating structure with an arbitrary emitter width is presented. The method provides high calculating accuracy of the characteristics of radiating structures based on chiral metamaterials with small computational resources. The results of calculating the longitudinal and transverse components of the current density distribution functions over the radiator are presented. The results were verified with the Feko software package. A good qualitative agreement of the current density distribution functions is shown. Practical application of the obtained results can be found in highly effective computer-aided design tools for the development of new-generation antennas which using in the modern communication systems, including 5G systems.

An experimental investigation of smooth matching transitions based on inhomogeneous sections of a microstrip transmission line with different wave impedances profiles was carried out in the present work. Comparative tests of smooth matching transitions prototypes are presented in order to confirm the theoretical data obtained by the optimal parametric synthesis method. The possibility of using synthesized piecewise linear transition to ensure good coordination in a fairly wide frequency range has been proven. It has been shown that fabricated inhomogeneous microstrip waveguide transitions provide matching in the frequency range from 1.2 to 2.7 GHz. It has been proven that the use of two-stage transitions allows a 1.5-times increase in the frequency matching band. Locally-optimized matching transitions near the lower boundary of the operating frequency range can give a significant gain in comparison with matching transitions with an exponential wave impedance profile for the same electrical length. The developed matching transitions can be used in the design of filters, matching transformers and connecting elements of the microwave frequencies transmission line.

A high-voltage light-emitting diode (LED) flip chip based on an AlInGaN heterostructure is developed and fabricated. The LED flip chip consists of 16 elements connected in series, each of which is a convential LED. The chip with a total area of 1.25 × 1.25 mm is intended for a working current of 20 mA and a forward voltage of 48 V. To improve the current-distribution uniformity over the active region of the chip elements and to minimize the losses of the element area occupied by the n-type contact, the n-type contact pads in them are arranged inside the p-type contact region due to the two-level metallization layout with an intermediate insulating layer of dielectric. The arrangement topology of the contact pads is developed using numerical simulation. An increase in the quantum efficiency of the chip is provided by the application of combinations of metals with a high reflectance at the LED emission wavelength, which are used when fabricating n- and p-type contacts as well as current-carrying strips.

Algorithms of the optimal arrangement of heat sources with volumetric heat release within regions of a complex geometric shape are considered. The distribution found has the minimum total power and provides the temperature in the given temperature corridor. Finite-dimensional approximations of the original problem are constructed in the form of a linear programming problem. A method is given for constructing a finite-difference scheme for solving the heat equation, as well as a brief description of the developed software modules for constructing grids and solving equations. Several computer experiments have been carried out using the developed programs.

Topics associated with color distortion that occurs in modern television systems are discussed in this article. The distortion of the image colors in comparison with the object colors for standard color correction circuits in a chamber channel television system is shown graphically. Considering that modern television screens have different color gamut, the magnitude of color distortion will be different for different models of TV screens. With a view of reducing the color distortion, a color correction method based on comparison of color coordinates in a colorimetric system of television cameras, with their colorimetric values measured in the CIE (Commission Internationale de l’Eclairage) system is proposed.

The M680I and M694V mutations located in the B30.2 pyrin domain are responsible for the manifestation of the most common forms of Familial Mediterranean fever. It is well known that a malfunction of the pyrin–caspase-1 complex is the main cause of inflammation in FMF. The purpose of this study was to identify possible changes in the tertiary structure of mutated B30.2 domain and to determine their potential consequences in the formation of the pyrin–caspase-1 complex. Using computer modeling, it was found that the above mutations change the tertiary structure of B30.2 domain, causing shifts of binding sites and altering the energy of interaction between B30.2 and caspase-1.

In this paper, we report on the development and fabrication of high power LED chips based on AlGaInN. These chips are meant for flip-chip mounting and have novel contact pad topology utilizing two-level metallization with the intermediate dielectric isolation. The size and shape of highly reflective ITO/Ag-based p-type and Ti/Ag based n-type contact pads were adjusted with the use of the numerical simulations of current spreading. As a result, the developed chip has 1 mm2 active area and series resistance as low as 0.3 Ω. The fabricated LEDs demonstrate emission power of 542 mW at 350 mA and the maximum external quantum efficiency equal to 60%. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The M680I and M694V mutations located in the B30.2 pyrin domain are responsible for the manifestation of the most common forms of Familial Mediterranean fever. It is well known that a malfunction of the pyrin-caspase-1 complex is the main cause of inflammation in FMF. The purpose of this study was to identify possible changes in the tertiary structure of mutated B30.2 domain and to determine their potential consequences in the formation of the pyrin-caspase-1 complex. Using computer modeling, it was found that the above mutations change the tertiary structure of B30.2 domain, causing shifts of binding sites and altering the energy of interaction between B30.2 and caspase-1.

A high-power AlGaInN light-emitting flip-chip crystal with a new configuration of contact pads is developed and fabricated. The implementation of a two-level metallization scheme with a dielectric insulating interlayer significantly improves the active-to-total area ratio of the heterostructure (to 78%). Numerical simulation of the current spread, employed when developing the chip topology, makes it possible to achieve high uniformity of the current distribution over the active-region area and to obtain small values of the differential resistance of the chip (0.3 Ω). Light-emitting diodes with the maximum external quantum efficiency (60%) and output optical power (542 mW) at a working pump current of 350 mA are fabricated on the basis of crystals developed in the study.

A method of synthesizing of smooth, broadband matched junctions is proposed that is based on numerical integration of a differential equation for the coefficient of wave reflection from inhomogeneities. Optimum profiles of the wave impedance and frequency dependences of the power reflection coefficient are obtained and analyzed. It is shown that the proposed method allows solution of the synthesis problem to be significantly optimized due to minimization of computation time.

The M680I and M694V mutations located in the B30.2 pyrin domain are responsible for the manifestation of the most common forms of Familial Mediterranean fever. It is well known that a malfunction of the pyrin-caspase-1 complex is the main cause of inflammation in FMF. The purpose of this study was to identify possible changes in the tertiary structure of mutated B30.2 domain and to determine their potential consequences in the formation of the pyrin-caspase-1 complex. Using computer modeling, it was found that the above mutations change the tertiary structure of B30.2 domain, causing shifts of binding sites and altering the energy of interaction between B30.2 and caspase-1.

A dispersion equation for the eigenwaves of a metallized two-layer waveguide with chiral and ferrite layers is obtained. The dispersion characteristics of this structure are analyzed.

One- and two-sided impedance approximate boundary conditions are obtained for a thin chiral layer with a coordinate surface described in generalized orthogonal curvilinear coordinates. The problem of diffraction of a plane electromagnetic wave by an infinite circular chiral-metallic cylinder is considered as an example illustrating the application of such conditions for calculation of reflecting structures with chiral layers. The main component of the field diffracted by the reflecting structure under study is calculated with the use of the approximate boundary conditions and by means of a rigorous approach, and the results obtained with the help of the two methods are compared.

Based on an analysis of various material equations describing artificial chiral media, it is shown that the specific optical rotation can be determined as a product of the chirality parameter and the wavenumber of an electromagnetic wave propagating in the chiral medium. It is pointed out that different approaches are used in investigations of optically active and artificial chiral media.

A rigorous solution is found for the problem of reflection of E- and H-polarized plane electromagnetic waves from a metal plane covered by a chiral layer of arbitrary thickness. The dependence of the electromagnetic wave reflection on the chirality parameter and the layer thickness is studied. The reflection of the depolarized component is examined. The results, obtained using two different forms of the constitutive relations for a chiral medium, are compared.

Acute poisoning with alcohols and cholinotropic preparations carboxyphosphamide and atropine (0.8 LD(50)) was modeled on male outbred mice weighing 18-24 g. The decrease in activity of natural killer cells was most pronounced after injection of atropine, but insignificant after treatment with ethanol. The inhibitory effect of ethylene glycol, methanol, and methanol on functional activity of natural killer cells in vitro directly depended on their concentration. The effects of alcohols in equimolar concentrations of 10, 100, and 500 mM were similar. Therefore, immunotoxicity of alcohols was associated with the action of their metabolites. The ability of products formed after biotransformation of ethylene glycol, methanol, and ethanol in equimolar concentrations to cause damage to natural killer cells decreased in the following order: glyoxylic acid>formic acid>acetaldehyde>glycolaldehyde>glycolic acid. T-Activin injected subcutaneously in doses of 2.5 and 5.0 microg/kg for 3 days normalized activity of natural killer cells suppressed after acute poisoning with alcohols and cholinotropic preparations.

In vitro experiments on splenocytes from noninbred mice showed that ethylene glycol, methanol, and ethanol dose-dependently suppressed functional activity of T and B cells. These compounds in equimolar concentrations (10, 100, and 500 mM) produced similar effects, hence their immunotoxicity is determined by their metabolites. The suppressive effects of alcohol biotransformation products to antibody-forming activity of T and B cells decreased in the following order: glyoxylic acid - formic acid - glycolaldehyde - glycolic acid - acetaldehyde. The effects of these substances were dose-dependent. Suppression of T cells was more pronounced.

The problem of scattering of E-and H-polarized plane electromagnetic waves by a metal cylinder covered with a chiral layer is solved by the method of partial regions. The scattering field is studied in the near and far zones. The correlation between the type of polarization of the incident electromagnetic wave and the magnitude of the depolarized component of the scattered field is considered.

The results of experiments on male mongrel mice showed that a three-day treatment with T-activin in a dose of 2.5 micrograms/kg restored the activity of natural killer cells reduced by acute poisoning (1 LD50) with ethylene glycol (EG), methanol (MeOH), and ethanol (EtOH). In a dose of 5 micrograms/kg, T-activin produced the same action in the test animals upon acute poisoning with dimethyldichlorovinyl phosphate (DDVP), carbophos (CP), dichloroethane (DE), acrylonitrile (AN), Acetonitrile (AcN), atropine (AT). The degree of suppression of the native killer cell activity by the above chemicals increases in the following order: EtOHEGMeOHCPATAcNDEANDDVP.

Acute poisoning with alcohols and cholinotropic preparations carboxyphosphamide and atropine (0.8 LD(50)) was modeled on male outbred mice weighing 18-24 g. The decrease in activity of natural killer cells was most pronounced after injection of atropine, but insignificant after treatment with ethanol. The inhibitory effect of ethylene glycol, methanol, and methanol on functional activity of natural killer cells in vitro directly depended on their concentration. The effects of alcohols in equimolar concentrations of 10, 100, and 500 mM were similar. Therefore, immunotoxicity of alcohols was associated with the action of their metabolites. The ability of products formed after biotransformation of ethylene glycol, methanol, and ethanol in equimolar concentrations to cause damage to natural killer cells decreased in the following order: glyoxylic acidformic acidacetaldehydeglycolaldehydeglycolic acid. T-Activin injected subcutaneously in doses of 2.5 and 5.0 microg/kg for 3 days normalized activity of natural killer cells suppressed after acute poisoning with alcohols and cholinotropic preparations.

In vitro experiments on splenocytes from noninbred mice showed that ethylene glycol, methanol, and ethanol dose-dependently suppressed functional activity of T and B cells. These compounds in equimolar concentrations (10, 100, and 500 mM) produced similar effects, hence their immunotoxicity is determined by their metabolites. The suppressive effects of alcohol biotransformation products to antibody-forming activity of T and B cells decreased in the following order: glyoxylic acid - formic acid - glycolaldehyde - glycolic acid - acetaldehyde. The effects of these substances were dose-dependent. Suppression of T cells was more pronounced.

One-sided approximate impedance-type boundary conditions for a thin chiral layer placed on a perfectly conducting plane are derived. With these conditions, the problem of incidence of a plane electromagnetic wave on a chiral structure is solved. Approximate formulas for the coefficients of reflection of the fundamental and depolarized components are derived for the case of the perpendicular polarization of the electromagnetic wave (the electric field strength is normal to the plane of incidence). A comparison with an exact solution to the problem of diffraction by this chiral structure is made.